Determining Genetic Diversity of Deshi Jute (Corchorus capsularis) for the Improvement of Fibre Yield and Associated Traits

Commercially important natural fibres considered as fiber of the future are cultivated in different south-east Asian countries including India and Bangladesh. Unfortunately, they are characterized by limited genetic variation in terms of yield, quality and susceptibility to diseases and pests. Therefore, genetic deviation studies are crucial to develop a successful cultivation program to develop varieties to meet the growing demand for domestic and foreign jute products. In our study, which was conducted at the Central Jute Research Experiment Station of Bangladesh Jute Research Institute (BJRI), during Kharif seasons of 2014. 44 Thirteen progenies (1546, 1548, 4311, 4328, 4330, 4337, 4339, 5007, 6702/A, 6702/B, 6772, 6787, 6790) and two check varieties CVL-1 and CVE-3 (developed from Bangladesh Jute Research Institute) were investigated to study the genetic variability, genetic diversity and degree of association of different component characters related to fiber yield. The seeds of experimental plant materials were grown in Randomized Complete Block Design with three replications. Statistical analysis was run to find out the genotypic and phenotypic variances, correlations and cluster analysis for fibre yield related traits namely plant height (m), base diameter (cm), stick weight (g), fiber weight (g). Highly significant differences were observed among the genotypes for all the characters. Cluster analysis divided the accessions and varieties into four cluster. From our evaluation it was revealed that the treatment number 4337/06, 4339/06 and 6702/A performed better in most of the cases than the control varieties CVL-1 and CVE-3. These accessions may be used as parents for future variety development program

An anatomical screening of white jute accessions for fibre content

The present study was conducted to evaluate the performance of 24 advanced lines of white jute and four check varieties ( CVL-1, CC-45, BJRI Deshi Pat-7 & BJRI Deshi Pat-8) for screening out high yielding and better quality fibre through an anatomical approach at JAES, Manikganj. The experiment was conducted in randomly complete block design (RCBD) with three replications. The cultivars revealed significant differences among them for all the characters with range of variability. The highest bark thickness (2.32 mm) was noticed by the accession C-5036 which performed significantly better than the two checks and lowest was recorded by C-5126 (1.07 mm). The variety BJRI Deshi Pat-8 observed significantly the highest number of pyramid (54.13) whereas the lowest was recorded by the varieties BJRI Deshi Pat-7 (28.23). The accession C-5117 showed significantly the highest number of layer (10.29) whereas the variety, BJRI Deshi Pat-7 showed significantly lowest number of layer (6.32). The accession C-2305(92.37) and C-12221 (91.19) significantly showed top two number of fibre bundle, however, the lowest number of fibre bundle was recorded by BJC-5105(42.79). The largest area of pyramid was observed by the accession C-5036 (46.85 sq. mm) whereas the lowest was showed by BJC-5105 (14.50 sq. mm). The differences between Phenotypic Coefficient of Variation (PCV) and Genotypic Coefficient of Variation (GCV) were little for all the characters indicating these characters were less influenced by the environment. Heritability and genetic advance (GA) were high for number of pyramid, number of fibre, bundle and Area of pyramid (sq.mm). Three accessions(C-12221, C-2305, C-5036) are showed the best performance than other accession on our screening program. These accessions are included in cluster V among the five clusters which exhibit the highest performance in all parameter except number of pyramid and may be used in further hybridization of jute

Assessment of the Levels of Pollution and of Their Risks by Radioactivity and Trace Metals on Marine Edible Fish and Crustaceans at the Bay of Bengal (Chattogram, Bangladesh)

Marine environmental pollution is a longstanding global problem and has a particular impact on the Bay of Bengal. Effluent from different sources directly enters rivers of the region and eventually flows into the Bay of Bengal. This effluent may contain radioactive materials and trace metals and pose a serious threat to the coastal environment, in addition to aquatic ecosystems. Using gamma spectrometry and atomic absorption spectrometry, a comprehensive study was carried out on the radioactivity (226Ra, 232Th, 40K, and 137Cs) and trace metal (Cd, Pb, Zn, Cu, Ni, Fe, Mn, and Cr) concentrations, respectively, in fish and crustacean species collected from the coastal belt of the Bay of Bengal (Chattogram, Bangladesh). The analysis showed a noticeable increment in the levels of different radioactive pollutants in the marine samples, although the consumption of the studied fish and crustacean species should be considered safe for human health. Anthropogenic radionuclide (137Cs) was not detected in any sample. Furthermore, the metal concentrations of a small number of trace elements (Pb, Cd, Cr) were found to be higher in most of the samples, which indicates aquatic fauna are subject to pollution. The estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TR) were calculated and compared with the permissible safety limits. It was found that consuming the seafood from the Bay of Bengal may cause adverse health impacts if consumption and/or means of pollution are not controlled

Variation Theory in Teaching and Phenomenography in Learning : What’s Their Impact When Applied in Engineering Classrooms?

Although phenomenographic research approach has been widely used by education researchers to investigate students’ learning, little attention has been paid to the relationship between a pedagogical approach adopted by teachers and students’ learning outcomes, particularly in engineering education. This experimental study proposes integrating variation theory as a pedagogical approach to a face-to-face classroom environment for teaching complex engineering contents and adapting a phenomenographic approach to evaluate students’ learning outcomes. The teachers who participated in the experimental group incorporated the variation theory in their teaching process. In contrast, the teachers in the control group, being ignorant of the variation theory, taught the same content to achieve the same specific learning outcome. Drawing on data from students’ written responses both from experimental and control groups, this article illustrates how teachers implemented variation theory in the classroom and its impacts on student learning. The implementation of variation theory was confirmed by classroom observation, and the variation in understanding the topic was emerged from students’ written responses and interview data through phenomenographic analysis. The findings indicate that teachers informed by variation theory use variation and invariance that creates necessary conditions for learning. This study demonstrates how, by incorporating variation theory, a faculty member designed different pedagogical approaches, which helps students conceptualize complex engineering topics more systematically than those who do not discern variation. The study concludes with theoretical, empirical, and pedagogic implications for teacher education in engineering